Wire bonding is a well-known method of interconnecting the terminations of an integrated circuit (IC) chip to corresponding pads of a chip carrier or circuit bearing substrate. Conventional wire bond pad arrangements have utilized rectangular pads for receiving the wire bond interconnections from the IC chip. IC chips that require a large amount of input and output interconnections typically are fabricated with terminations having a very fine center-to-center pitch, e.g., seven mils (0.1778 mm).
The very fine pitch of the IC terminations in combination with the minimum pad width and pad separation of the rectangular wire bond pads required for acceptable wire bond manufacturing yields can cause an overly wide sweep of the wire bonds near the corners of the chip. The overly wide sweep causes the angle between the wire bond and the edge of the chip to be less than the minimum angle considered acceptable, e.g., forty-five degrees. Wire bond angles below the minimum acceptable angle are accompanied by a sharp increase in defects due to shorted and/or broken wire bonds.
Thus, what is needed is a wire bond pad arrangement that reduces wire bond sweep near the corners of the IC chip without violating the minimum pad width and pad separation requirements for acceptable wire bond manufacturing yields.